Very nice find! You may want to try some leather conditioner on the case. The oils in it will help moisturize the leather, and keep it from deteriorating any more than it already has. Use on both interior and exterior surfaces.
Nice! You might be able to find a replacement case.
I've seen light seal kits being sold. But the guy who owned our camera store (that had been around since I was a kid til he retired) suggested using the soft side of Velcro, cut into strips. I was in need of a new mirror bumper, worked great for that, but never tried it for seals. Probably a matter of whether you'd want to fool with cutting long strips to fit or get a kit of precut seals.
Tape's a good temporary measure, til you get tired of untaping to load/unload film!